Automatic tail end cropping device



Jan. 12, 1965 N. A. WILSON AUTOMATIC TAIL. END CROPPING DEVICE 2 Sheets-Sheet 1 Filed March 8, 1963 0 INVENTOR.

Norman H. ZZ/iZson 2o 20 BY 22 W, m r fliwq H orneys Jan. 12, 1965 N. A. WILSON AUTOMATIC TAIL END CROPPING DEVICE 4 2 Sheets-Sheet 2 Filed March 8, 1963 4 a R A E H o s w mm" mm R C L Wm T M 3 om mu c T [G o n wu 8 A H mm m G Wklll||hl |l.| I'H 5H NH 5 m w? m wa wh lww mm i lllm M m RE .I l l WM 8 E m A N mm m w z z w 4 A1 a 5% In 0 NM... on: m M xm H am: on n car INVENTOR Norman H; Wilson BY M. 642734 9- W H orneys United States Patent 3,165,026 AUTOMATEC TAIL END CRGPHNG DEVIQE Norman A. Wiison, Westhoro, Mass, assignor to Morgan Construction Qompany, Worcester, Mass, a corporation of Massachusetts Filed Mar. 8, 1963, Ser. No. 263,763 4 Claims. ((31. 83362) This invention relates to rod mills and more particularly to an automatic tail end cropping device for removing off-gauge end sections of moving rod subsequent to the final rolling operation but prior to the coiling operation.

Under the present practice of rod rolling, the tail end of a rod is usually off-gauge (either under-sized or oversized) as it leaves the finishing stands of the rolling mill. This is due in part to the difference in temperature between the front and rear portions of the rod. At the present time, this off-gauge portion is manually removed by an operator following the coiling operation. At that time, as the coil is moving along a hook carrier, the operator grasps several strands of the rod and cuts them off with hand clippers. The number of strands to be cut in this fashion will be determined by the operator through the use of a hand micrometer. Since coils are deposited at frequent and regular intervals in a multi-strand mill, this final gauging and cutting operation requires the constant attention of at least one operator and perhaps two or more.

While attempts have been made to crop the off-gauge tail end of the rod with a shear while it is running in the mill, they have not proved entirely successful. This failure has been due primarily to a lack of ability accurately to measure the cross-sectional dimensions of moving rod.

In accordance with the present invention selected cross-sectional dimensions of moving rod are quickly and accurately measured through the application of infrared micrometers positioned adjacent each strand. The gauges instantaneously measure the rod and emit error signals which are then compared with acceptable gauge tolerances. When the error signals exceed these acceptable gauge tolerances, they may be used to actuate various gauge control mechanisms throughout the mill and are here applied in combination with tail end selection circuits to control the operation of the cropping shear. Where a final gauging operation shows that a portion of the rod remains off-gauge after having passed through the finishing stands, the error signals are used to crop the off-gauge portion by actuating shears positioned downstream from the gauges at a point prior to the final coiling operation and in time delayed relation to the sensed gauge and position of the tail end of the rod.

Consequently, an object of the present invention is to avoid the necessity of manually gauging and cropping off-gauge end portions of a rod after it has been coiled by automatically performing this operation while the rod is still in the mill.

Another object of this invention is to reduce operating costs by eliminating the need of positioning operating personnel in the vicinity of the hook carriers in order to perform the final operation of manually gauging and cropping off-gauge portions of the coiled rod.

These and other objects of the present invention will become more apparent as the description proceeds with the aid of the accompanying drawings in which:

FIG. 1 is a schematic diagram illustrating the positional relationship of the control components comprising the automatic tail end cropping system with respect to the rod reels and finishing stands of a two-strand mill;

FIG. 2 is a circuit diagram of the automatic tail end cropping system chosen for purposes of disclosure.

3,l6i5,2 Fatented Jan. 12, 1955 Referring now to FIG. 1, the strands 2 containing moving rod are shown passing through looping stands 4, 6 and 8 and finishing stands 10. The presence of the rods is detected at a point immediately subsequent to their passage through looping stand 8 by rod detectors 12. As previously stated, the tail end of the rod is usually olf-gauge as it leaves the finishing stands 10. Consequently infrared micrometer gauges 14 are positioned at a point immediately following finishing stands 10 in order to measure the cross-sectional dimensions of the rods as they pass this point. Drum shears 16 are then positioned downstream from infrared micrometer gauges 14 and are actuated by delayed error signals emitted by the infrared micrometers in order to crop off-gauge end portions prior to the final reeling operation. The on-gauge portions of the moving rods 2 are then conducted through pipe guides 18 to reels 20 where they are coiled and carried off by a hook carrier (not shown). The cropped portions are deposited in crop chute 22 for subsequent removal.

The circuit of FIG. 2, which provides the control sequence of the invention, will now be described. The rod detector 12 operates a normally open switch 24 and a normally closed switch 26 and actuates these switches to their opposite condition upon the detection of a rod at the location of detector 12. The switch 24 is connected to supply power when closed to the coil of the time delay relay 311 which operates a normally closed contact 32 to close promptly and open 0.25 second after the coil of time delay relay 30 is de-energized. The normally closed contact 26 and the normally open contact 32 are connected in series to energize, when both contacts are closed, the coil of a relay 34 which operates normally open contacts 36 and 38. The infrared micrometers 14 are arranged to actuate normally open contact 28 whenever rod is detected at the location of the micrometers 14 and to actuate normally open contact 42 whenever the size of the rod present at the location of the micrometer 14 is off gauge. An alternate energizing circuit for the coil of relay 34 is provided by the serial connection of contacts 28 and 36 whenever both of these contacts are closed. The serial connection of contacts 28, 42 and 38 provide an energizing circuit for the coil of a relay 44 whenever all three contacts are closed. The relay 44 operates normally open contacts 45 and 46. The relay 46 is connected to start a timer 50 through a preset timing cycle of predetermined length in relation to the running speed of the mill as hereinafter described. The timer. 50 operates at the end of its timing cycle to open normally closed switches 48 and 52 and to close normally open switch 58. The normally closed switch 48 is serially connected with normally open switch 45 to provide a holding circuit for the relay 44 whenever both switches are closed. The normally closed contact 52 energizes the coil of a time delay relay 54 which when actuated closes a normally open switch 56 and maintains it closed for a period of 0.25 second after the coil of time delay relay 54 is deenergized. The switch 56 is in series with switch 58 and connected to a circuit to operate the shear 16 whenever both switches 56 and 58 are closed. The closure of both switches 56 and 58 also energizes the coil of a relay 60 which operates normally open reset contact 62 to reset the timer 50 to its initial condition for the resumption of operation in the next bar that is processed. The circuit of FIG. 2 is duplicated for the control of each strand in the mill.

The sequence of operation of the above mentioned components will now be described. Since each strand is controlled in the same manner, the description will proceed with reference to only a single strand. As the head end of a rod passes under rod detector 12, its presence is detected and a presence signal from detector 12 actuates switch 24 to a closed position and switch 26 to an open position. The head of the rod then proceeds through the finishing mill 16 and arrives at the infrared micrometer 14,-where a presence signal from the micrometer 14 closes switch 28. With switch 24 closed, a voltage is impressed across time delay relay 30, closing switch 32. As the rod leaves rod detector 12, switch 24- is opened and switch 26 closed. Because of the time delay in relay 3%), switch 32 remains closed for an additional 0.25 second following the loss of voltage across relay 3%. With both switches 26 and 32 closed for this brief interval, a voltage is impressed across relay 34, resulting in the closure of switches 36 and 38. Once relay 34 is energized, switch 36 holds relay 34 energized as long as rod is present in the micrometer 14 to maintain switch 28 closed.

As the rod passes under infrared micrometer 14, its cross-sectional dimension is measured and compared with acceptable gauge tolerances. When the rod exceeds these tolerances, an error signal operates to close switch 42 providing an end of the rod has been sensed by rod detector 12 to close switch 26; otherwise an off-gauge signal from micrometer 14 has no efiect on relay 44 and the timing cycle for a cut is not initiated. If an end of the rod is sensed and switch 26 is closed but no off-gauge signal is produced by micrometer 14, relay 44 is never energized due to the failure of contact 42 to close. Thus if there should be no off-gauge tail end, the timing cycle to operate the shear will not be initiated and the control system reverts to initial conditions to process the next rod.

With switches 23, $2 and 38 closed, a voltage is impressed across relay M with the result that switches 45 and 46 are closed. Since switch 48 is normally closed, current is now allowed to flow through switches 45 and 48, establishing a holding circuit for relay 44. With the closing of switch 46, timer 50 is actuated and the timing cycle started. The length of the timing cycle is a function of the speed of the rod and the distance between the infrared micrometers l4 and the drum shears 16 and 1 the timer 50 is set to correspond to the length of time necessary for the'ofi-gauge portion of the rod to pass from the infrared micrometers 14 to a point under the drum shears 16.

Since switch 52. is normally closed, a voltage is impressed across time delay relay 54, resulting in the closing of switch 56. Switch 56 will remain closed for 0.25 second after the loss of voltage across relay 54 because of the built in 0.25 second delayed drop-out. Upon the expiration of the timing cycle of timer 50, switches 48 and 52 are opened and switch 58 closed. Because of the above mentioned drop out in time delay relay 54, although the opening of switch 52 results in a loss of voltage across relay 54, switch 56 remains closed for 0.25 second. Since both switches 58 and 56 are closed for a brief interval, the shear circuit is closed and a signal emitted to actuate the drum shears and crop the olfgauge portion of the rod. Switches 56 and 58 also close the circuit to energize reset relay 60 which closes contacts 62 to reset the timer 50 and revert switches 48, 52 and 58 to normal.

The appearance of a new rod at rod detector 12 opens relay 26 and closes relays 24 and 32. When the tail end leaves infrared micrometer 14, relay 2% is opened, resulting in a loss of voltage to coil 34 and the opening of contacts 36 and 38. Subsequent to the expiration of the timing cycle of timer 50, switches 48 and 52 are reopened, in turn resulting in the opening of switches 45 and 46 and the resetting of timer 50. Since switch 56 is actuated by time delay relay 54, it also remains closed for only a brief interval before re-opening in preparation for the next cutting cycle.

Thus it can be seen that the system will automatically measure and crop oil-gauge end sections of moving rod and then reset itselffor the next oncoming rod.

It is my intention to cover all changes and modifications of the example of the invention chosen for purposes of disclosure which do not constitute departures from the spirit and scope of the invention.

I claim:

1. Means for removing off-gauge tail end portions of moving rod in a rod mill comprising the combination of a presence sensing device positioned adjacent the strand at a first position along the pass line, said presence sensing device emitting a presence signal when the tail end of the rod leaves said first position, infrared micrometer gauges responsive to said presence signal positioned adjacent the strand at a second position along the pass line for measuring the gauge of said moving rod, said second position being downstream a predetermined distance from said first position, said gauge capable of comparing the measured value of the rod gauge with acceptable rod gauge tolerances in order to emit an error signal when said measured rod gauge exceeds said tolerances, cutting means responsive to said presence signal and error signal for cropping moving rod, said cutting means positioned adjacent said strand at a third position along the pass line downstream from said second position, and means for delaying said error signal until said offgauge portion is within operating range of said cutting means.

2. The combination as set forth in claim 1 wherein said distance from said first position to said second position is equal to the length of the end portion of the rod to be measured by said infrared micrometer gauges.

3. Means for automatically removing the off-gauge tail end portions of moving rod in a multi-strand rolling mill comprising the combination of rod detectors positioned adjacent each said strand at a first position along said pass line in order to detect the presence or absence of a rod in a strand at said first position, said detectors omitting presence signals when the tail end of rods leave said first position, infrared micrometer gauges positioned adjacent each said strand at a second position along the pass line downstream from said first position, said infrared micrometer gauges capable of measuring the cross-sectional dimensions of the moving rod in order to emit error signals when said cross-sectional dimensions exceed acceptable gauge tolerances, the operation of said infrared micrometers being controlled by said presence signals, cutting means responsive to said presence signal and error signals for cropping and removing the off-gauge end portions of said moving rod, said cutting means positioned at a third position along the pass line downstream from said second position, and means for delaying the transmission of said error signals to said cutting means until the elf-gauge portion of said rod arrives at said third position.

4. In a rolling mill, means for automatically cropping the oil-gauge tail end portions of moving rod prior to the coiling operation, said means comprising rod detectors positioned at a point along the pass line, said rod detectors emitting presence signals when the tail end of the rod passes said point, infrared micrometer gauges positioned along the pass line at a point downstream from said rod detectors, said gauges activated by said presence signals and capable of measuring the cross-sectional dimensions of the moving rod, said gauges emitting error signals when the cross-sectional dimensions of said moving bars exceed prescribed tolerances, drum shears positioned adjacent said pass line at a point downstream from said infrared micrometer gauges, the application of said drum shears to said moving rod controlled by said error signals and said presence signals and means for delaying the transmission of said error signals to said drum shears until the oft-gauge end portion of the rod passes thereunder.

No references cited. 

1. MEANS FOR REMOVING OFF-GAUGE TAIL END PORTIONS OF MOVING ROD IN A ROD MILL COMPRISING THE COMBINATION OF A PRESENCE SENSING DEVICE POSITIONED ADJACENT THE STRAND AT A FIRST POSITION ALONG THE PASS LINE, SAID PRESENCE SENSING DEVICE EMITTING A PRESENCE SIGNAL WHEN THE TAIL END OF THE ROD LEAVES SAID FIRST POSITION, INFRARED MICROMETER GAUGES RESPONSIVE TO SAID PRESENCE SIGNAL POSITIONED ADJACENT THE STRAND AT A SECOND POSITION ALONG THE PASS LINE FOR MEASURING THE GAUGE OF SAID MOVING ROD, SAID SECOND POSITION BEING DOWNSTREAM A PREDETERMINED DISTANCE FROM SAID FIRST POSITION, SAID GAUGE CAPABLE OF COMPARING THE MEASURED VALUE OF THE ROD GAUGE WITH ACCEPTACLE ROD GAUGE TOLERANCES IN ORDER TO EMIT AN ERROR SIGNAL WHEN SAID MEASURED ROD GAUGE EXCEEDS SAID TOLERANCES, CUTTING MEANS RESPONSIVE TO SAID PRESENCE SIGNAL AND ERROR SIGNAL FOR CROPPING MOVING ROD, SAID CUTTING MEANS POSITIONED ADJACENT SAID STRAND AT A THIRD POSITION ALONG THE PASS LINE DOWNSTREAM FROM SAID SECOND POSITION, AND MEANS FOR DELAYING SAID ERROR SIGNAL UNTIL SAID OFFGAUGE PORTION IS WITHIN OPERATING RANGE OF SAID CUTTING MEANS. 